Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi or more and a ceiling of 3,000 ft or more. Only observations between sunrise and sunset are taken into account.
Marginal VFR conditions (%)
Month
Average
2024
2023
2022
2021
2020
January
78.3
83
82
70
74
85
February
81.6
87
83
82
80
71
March
87.1
91
86
83
90
80
April
84.8
92
81
94
87
May
93.9
100
90
93
96
June
89.7
84
91
86
93
July
89.6
85
92
94
81
August
91.8
80
91
91
89
September
88.3
84
85
90
87
October
85.9
80
95
92
80
November
80.2
77
89
77
81
December
81.1
93
85
76
81
Average
86.7
87.7
85.5
86.0
87.3
85.1
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.
Maximum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-7.5
-7
-5
-11
-5
-5
February
-5.9
0
-5
-7
-4
-4
March
1.0
4
2
-1
3
2
April
7.8
9
8
12
7
May
17.2
16
19
18
18
June
21.2
22
20
24
24
July
24.8
25
25
24
26
August
23.4
21
23
26
23
September
18.9
20
18
19
18
October
12.2
15
15
14
10
November
2.2
1
3
4
5
December
-4.4
-5
0
-3
-1
Average
8.4
-1.5
10.6
9.0
11.0
10.3
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-16.3
-14
-12
-21
-12
-14
February
-16.7
-11
-11
-16
-17
-17
March
-9.4
-3
-5
-8
-10
-8
April
-2.5
2
1
0
-3
May
5.0
7
8
5
4
June
9.6
13
12
12
10
July
13.7
18
15
12
16
August
13.4
16
16
15
12
September
8.7
13
10
9
6
October
3.0
8
4
4
2
November
-6.9
-5
-3
-4
-4
December
-13.3
-8
-5
-13
-9
Average
-2.9
-9.5
3.8
0.7
0.1
-1.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
26.9
29
26
25
29
16
February
22.0
16
23
35
20
24
March
15.9
13
19
34
14
15
April
19.0
22
25
13
15
May
10.0
10
14
9
7
June
13.1
26
19
16
8
July
7.2
19
11
5
11
August
8.1
21
17
3
10
September
11.3
16
13
13
15
October
16.1
18
12
8
22
November
23.0
30
27
15
19
December
20.8
38
27
20
22
Average
16.2
17.2
20.9
21.5
12.7
14.2
Precipitation during daylight period
Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.
Wind speed (knots)
Month
Average
2024
2023
2022
2021
2020
January
5.0
4
3
5
5
5
February
5.7
5
4
5
6
6
March
6.5
7
5
6
7
6
April
6.8
6
8
7
7
May
6.5
8
6
6
7
June
5.7
5
6
6
6
July
5.1
4
6
6
5
August
4.8
5
5
5
5
September
4.5
4
6
5
5
October
5.0
4
5
5
5
November
5.2
5
5
5
5
December
4.7
3
6
5
4
Average
5.5
5.3
4.9
5.6
5.5
5.5
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
2020
January
215°
279°
289°
276°
266°
February
274°
138°
300°
253°
257°
March
256°
307°
274°
275°
295°
April
247°
007°
126°
272°
May
322°
240°
289°
283°
June
125°
152°
246°
213°
July
241°
239°
255°
207°
August
232°
216°
250°
255°
September
182°
309°
272°
264°
October
231°
215°
145°
291°
November
274°
279°
256°
286°
December
150°
286°
270°
275°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.